The rectum is the last section of the gut, and this is where the faeces are temporarily stored. As the rectum gets fuller, stretch receptors in the walls of the rectum start firing, and eventually trigger the act of defecation.

An essential part of this process is the thin layer of mucus that coats the inside wall of the colon and rectum. It acts as a lubricant. Check it out the next time you see a dog doing a poo.

For a few moments the fresh poo is shiny — that's the light reflecting off the mucus. Then the mucus evaporates, and the poo takes on a dry dull appearance. Bigger animals have thicker mucus.

This mucus is the key to how it can take roughly the same amount of time for the defecation event of a mouse, or an elephant.

Mucus is the key

The mucus has a strange property called "shear-thinning". It can split into layers, which can simultaneously move apart from each other, while still having some stickiness (or adhesion) to each other.

This strange splitting property was part of the mathematics that the scientists had to incorporate into their peer-reviewed study.

They also had to incorporate many other factors, including the ability of the pieces of faeces to flow (or distort) under pressure.

They found that the way faeces leaves your body is not like toothpaste being squeezed out of a tube — it's more like a little bullet sliding through a hose.

Conditions such as inflammatory bowel disease and irritable bowel syndrome cost billions of dollars annually in the USA to treat. And the wildly altered bowel habits can make life hell for sufferers.

We need studies like this one to better understand these conditions — and then offer effective treatments.

So we study poo to add to our knowledge of bowel basics, not just because we love mouse faeces to pieces.

In carving her own path to the top of the political game, Julie Bishop has learned to be as bold, confident and skilful as anyone in Parliament — traits all on display in a cutting final speech, writes Annabel Crabb.